Structural highlights
Disease
[XYLT1_HUMAN] XYLT1-CDG;Desbuquois syndrome. The disease is caused by mutations affecting the gene represented in this entry. The gene represented in this entry acts as a disease modifier.
Function
[XYLT1_HUMAN] Catalyzes the first step in biosynthesis of glycosaminoglycan. Transfers D-xylose from UDP-D-xylose to specific serine residues of the core protein. Initial enzyme in the biosynthesis of chondroitin sulfate and dermatan sulfate proteoglycans in fibroblasts and chondrocytes.[1] [AMBP_HUMAN] Inter-alpha-trypsin inhibitor inhibits trypsin, plasmin, and lysosomal granulocytic elastase. Inhibits calcium oxalate crystallization.[2] Trypstatin is a trypsin inhibitor (By similarity).[3]
Publication Abstract from PubMed
Proteoglycans (PGs) are essential components of the animal extracellular matrix and are required for cell adhesion, migration, signaling, and immune function. PGs are composed of a core protein and long glycosaminoglycan (GAG) chains, which often specify PG function. GAG biosynthesis is initiated by peptide O-xylosyltransferases, which transfer xylose onto selected serine residues in the core proteins. We have determined crystal structures of human xylosyltransferase 1 (XT1) in complex with the sugar donor, UDP-xylose, and various acceptor peptides. The structures reveal unique active-site features that, in conjunction with functional experiments, explain the substrate specificity of XT1. A constriction within the peptide binding cleft requires the acceptor serine to be followed by glycine or alanine. The remainder of the cleft can accommodate a wide variety of sequences, but with a general preference for acidic residues. These findings provide a framework for understanding the selectivity of GAG attachment.
Structural Basis for the Initiation of Glycosaminoglycan Biosynthesis by Human Xylosyltransferase 1.,Briggs DC, Hohenester E Structure. 2018 Apr 10. pii: S0969-2126(18)30095-9. doi:, 10.1016/j.str.2018.03.014. PMID:29681470[4]
From MEDLINE®/PubMed®, a database of the U.S. National Library of Medicine.
References
- ↑ Muller S, Schottler M, Schon S, Prante C, Brinkmann T, Kuhn J, Gotting C, Kleesiek K. Human xylosyltransferase I: functional and biochemical characterization of cysteine residues required for enzymic activity. Biochem J. 2005 Mar 1;386(Pt 2):227-36. PMID:15461586 doi:http://dx.doi.org/BJ20041206
- ↑ Atmani F, Khan SR. Characterization of uronic-acid-rich inhibitor of calcium oxalate crystallization isolated from rat urine. Urol Res. 1995;23(2):95-101. PMID:7676539
- ↑ Atmani F, Khan SR. Characterization of uronic-acid-rich inhibitor of calcium oxalate crystallization isolated from rat urine. Urol Res. 1995;23(2):95-101. PMID:7676539
- ↑ Briggs DC, Hohenester E. Structural Basis for the Initiation of Glycosaminoglycan Biosynthesis by Human Xylosyltransferase 1. Structure. 2018 Apr 10. pii: S0969-2126(18)30095-9. doi:, 10.1016/j.str.2018.03.014. PMID:29681470 doi:http://dx.doi.org/10.1016/j.str.2018.03.014
